Length Change Of The Pipe System - Bosch FCS-320-TM Operation Manual

FCS-320-TM Aspirating Smoke Detector
NOTICE!
Do not use pipe clips with rubber inserts since these do not allow length extensions and the
pipe system could thus bend or even tear.
5.
NOTICE!
On completion, test the pipe system:
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5.1

Length Change of the Pipe System

Length changes (extensions and reductions) of the pipes are caused by temperature changes.
Temperature increases cause lengthening of the pipes, temperature drops cause shortening
of the pipes. The length change must be given particular consideration if the temperature of
the pipe system at the time of installation deviates from the normal operating temperature.
The length change can be calculated using the following formula:
where
ΔL
L
ΔT
δ
PVC
δ
ABS
For example, a temperature change of 10 °C on a 10 m-long PVC pipe causes a length change
of 8 mm.
Mounting clamps
PVC pipe clips are used as standard for installing the pipe system. These clips do not allow
any length extensions.
Figure 5.1 Overview of mounting clamps
Bosch Sicherheitssysteme GmbH
Close open pipe ends with an end cap.
For tightness
For fault-free connections
For correct planning of the air sampling openings.
= Length change in [mm]
= Length of the pipe to be calculated in [m]
= Maximum temperature difference in [°C]
= 0.08 mm/m x °C
= 0.101 mm/m x °C
1 2
1 Standard mounting clamps for 25 mm pipe
2 Plastic mounting clamps for 25 mm pipe, for
length changes and temperatures of up to -40 °C
3 Spring steel clamp for 25 mm pipe, for high-rise
3
warehouses and temperatures of up to -40 °C
Operation Guide
Installation of the Pipe System | en
F.01U.130.928 | 1.0 | 2009.11
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